Izhar Zahavi

Effect of Three Days Starvation on the Phagocytic Activity of Rat Peritoneal Macrophages

To examine the effect of starvation on the phagocytic activity of rat peritoneal macrophages, 8 animals were kept for 3 days on water supply only. The cells showed an increased capacity for superoxide anion production and a marked decrease in their ability to engulf latex particles. The corticosterone level of the fasting animals was markedly increased, an observation suggesting that the alteration of macrophage function could be hormonally mediated. The findings in the present study indicate that the decreased phagocytic capacity of peritoneal macrophages following starvation may be one of the factors responsible for the increased susceptibility to infections in malnourished individuals.

Elevated serum ferritin level in acute myocardial infarction

Serum ferritin level was determined in 20 patients with acute myocardial infarction (AMI) during the first 10 days post infarction. Starting on the second day, a gradual increase in serum ferritin level was detected, reaching a maximum of four times the initial level on the sixth day after the infarction. In addition, a significant increase in ferritin content was found in the peripheral blood monocytes on the fifth day after the event. The control group comprised six patients suffering from chest pains not due to AMI. In all of them the serum ferritin level was found to be within normal limits. Peripheral blood monocytes derived from healthy individuals incubated with hydrocortisone, showed a significant enhancement of their ferritin content, a finding suggesting that these cells activated by steroids during stress could be a source of the increased serum ferritin level following AMI. It is concluded that measurement of serum ferritin may be used as a complementary tool for confirming the diagnosis of AMI.

Adenosine stimulates ANP expression in cultured ventricular cardiomyocytes.

Adenosine protects the ischemic myocardium by coronary vasodilation and the depression of heart rate and contractility, improving myocardial energy balance. Adenosine effects on the myocardium are mediated predominantly by the type A1 receptors. Atrial natriuretic peptide (ANP), a vasodilator and regulator of blood volume, is secreted from either atrial or ventricular myocytes in response to cellular distention. In vivo, adenosine infusion has been shown to induce a rapid increase in plasma ANP, independent of blood pressure. We examined the possibility that adenosine enhances ANP-gene expression in cardiac myocytes. Administration of adenosine (10 microM) to cultured neonatal rat cardiomyocytes led to a 1.7-fold increase (p = 0.014, n = 9) in the abundance of ANP messenger RNA (mRNA) within 30 min, as measured by Northern blot hybridization. No such increase was obtained when adenosine was coadministered with 8-cyclopentyl-1,3dipropylxanthine (CPX, 10 microM), an adenosine A1-receptor antagonist. Our results point at adenosine as regulator of ANP mRNA level in cardiac myocytes.

Ultrastructural and chromosomal studies in a patient with hypergranular (M3) promyelocytic leukemia with two abnormal clones.

The internal and surface ultrastructural features of the white blood cells of a patient with hypergranular (M3) promyelocytic leukemia are described. Cytogenetical studies of the patient’s cells revealed the presence of two abnormal clones: the first, 45, XY, -7, and the second with an interstitial deletion in the long arm of chromosome 15 with break points at q22 and q26.

X-Ray Microanalysis of the Element Content in the Hearts of Mice Treated with Digoxin

The element content was detected by X-ray microanalysis in the hearts of mice treated with daily doses of 0.075 microgram digoxin for 12 days and compared with that of controls. Statistically significant differences were found for K and S, which were lower, and for P, which was higher following treatment with digoxin. In the sera of the treated mice Mg was slightly lower, whereas Ca and K levels were found to be elevated in comparison with those of nontreated animals. A possible explanation for these findings is discussed.

Effect of verapamil on platelet surface ultrastructure and calcium content

The effect of verapamil on the surface ultrastructure and calcium content of human platelets was studied by scanning electron microscopy and X-ray microanalysis. The results showed that the drug prevents platelet pseudopodia formation and causes a dose-dependent inhibition of platelet calcium concentration. The significance of these findings in the explanation of the inhibitory effect of verapamil on platelet aggregation is discussed.

In vitro Colony-Forming Cells in Embryonic Mouse Liver, Spleen and Peripheral Blood

The number of in vitro colony-forming cells (CFC) was examined in embryonic livers, spleens, and peripheral blood of C57B1/6J mice from the 12th to the 19th day of gestation. Peaks of CFC in the liver and spleen were noted on days 13, and 15, respectively, whereas the number of CFC in the peripheral blood remained almost constant. The possibility that CFC in the embryonic mouse are produced both in the yolk sac and in other hemopoietic sites is discussed.

The in vitro effect of pirprofen on the surface ultrastructure and function of human platelets

SummaryThe in vitro effect of pirprofen (Rengasil), an antiinflammatory agent, on the surface ultrastructure and function of human platelets was examined and compared with that of acetylsalicylic acid (Aspirin, ASA), and diclofenac sodium (Voltaren, DS). Incubation with pirprofen induced formation of long, neddle-shaped pseudopodia, a phenomenon observed also after incubation of the cells with DS. In contrast with ASA and DS, pirprofen induced a marked increase in platelet protein synthesizing capacity. The drug decreased the platelet aggregation to a degree similar to that of ASA and DS. The release of platelet factors 3 and 4 and the level of β-thromboglobulin following incubation with the drug remained unaltered.

Cardiopulmonary Fistula as a Late Complication Following Repair of Tetralogy of Fallot

Abstract A patient is described in whom a cardiopulmonary fistula was responsible for repeated bouts of massive hemoptysis. The fistula developed 6 years after a corrective operation for tetralogy of Fallot, as a result of a postoperative staphylococcal infection of the mediastinum and operative wound. At operation an abnormal communication between the right ventricle and the upper lobe of the left lung was demonstrated. A Teflon graft used to enlarge the outflow tract of the right ventricle at the time of the tetralogy correction operation was found to be completely detached and floating free in a small lung abscess adjacent to the right ventricle. Left upper lobectomy and closure of the fistula with reconstruction of the right ventricle was performed. The patient made a complete recovery. The importance and value of repeated bronchoscopic examinations in similar conditions is stressed.